I beg to differ with many posters here, while also agreeing with them in most of the things they say - the difficult area for objective analysis is the human element.
You can have objective game scoring, it just takes too much aptitude than the average person is willing to invest. It requires you to be able to step back from the experience and have a properly open-minded approach. Sounds easy enough, but why don't we see this? For all the reasons mentioned above, the human element in the system prevents the system from functioning because the human element has needs and requirements beyond the stated goal.
For example, take games like Dragon Age or Pillars of Eternity. If you were to objectively score them on their success at providing interesting combat, any correctly objective review would mark them down very heavily, possibly as much as 0.7 off the final 10, so the games cannot be, objectively, a 9.5 or above before you've even closely analysed anything else.
The objective part of the combat is the extent to which the game succeeds in what it was trying to achieve - not the subjective notion of whether you enjoyed the combat.
Now take a near universally accepted crappy game, Sacred 3, and apply the same rationale - did the game's combat achieve what it was supposed to - as in, work faultlessly with the associated mechanics, provide enough of an interesting and varied experience for the kind of person who likes that form of combat? And, objectively, Sacred 3 could well have a better combat score for the purposes of review.
Because you would be buying the game based on the description of the play-style and intent, not just because it's something that claims to be an RPG.
Though rarer, a fan of the Sacred 3 method is generally a happy camper, they got what they paid for. The people who bought PoE and DA:I would be fully justified in feeling they did not get what they paid for, because both these games advertised highly tactical combat as a sales promotion and both apply mechanics/gameplay which is/are underutilised for this purpose. And that's what a review should be, a buyer's guide.
For all three games, however, there's also the human element of the titles being associated with other games - they are all three supposedly sequels. A fully objective review doesn't care about this, sequel or not, you should have researched objective reviews before you purchased the game - tough puppies if your beloved has metamorphed into Frankenstien's Monster, that's not objective, that's you being depressed because something you like isn't there.
The objective scoring system just looks at what the game prioritises and scores based on how it implements its priorities. And, yes, boring is an objective reasoning, because boring is a fault of a known element. People might have different boredom thresholds, but boring is still pretty obvious to anyone with a sense of empathy.
The best time to make an objective review is a few days after completing the game for the first time, while every thought you had while playing is still fresh, but you've also had time to cool down from the exhilarating/tedious end boss.
However, humans are humans. If objectivity produces a world where Sacred 3 scores higher than Pillar of Eternity, are you absolutely sure you wish to follow true objectivity?
Is 100% objectivity as equally incorrect as 100% subjectivity…? (dun, dun, dahhhh)
